I assume you mean charms such as weakness, dispels, or the bad juju or efreet -90 charm. There is no current spell to remove all negative charms. The closest thing to what you want is dimension shift. This is a level 75 myth spell that allows you to place all charms on you (including the positive ones) onto your minion. It costs six pips however and is hardly worth the effort to cast in my opinion.
